When the next major content patch launches we will be introducing epic quality gems and updating the perks for each profession. Please keep in mind that any of this information may see further changes before the patch launches.

The design recipes for cutting epic gems will be made available for purchase with Dalaran Jewelcrafter’s Tokens and there are several ways to obtain raw epic gems:

Coinciding with the implementation of epic gems and the gain that Blacksmiths will receive through their perk from these new gems, we have gone through all of the perks in every profession and increased their values to match up accordingly.

Alchemy

The Mixology benefits from Northrend elixirs and flasks have been increased
Added a new pattern for Flask of the North, usable by players with a high alchemy skill. The recipe is purchased from the honor potion vendor. The Flask of the North increases your spell power, attack power, or Strength for 1 hour, and is usable in arenas. It is not consumed when used.
Endless Healing Potion and Endless Mana Potion no longer usable in arenas. Amount of health and mana has been increased, and the cooldown reduced. They are still usable everywhere else.

Blacksmithing

No changes will be made to this profession; it will continue to have the 2 additional prismatic sockets (which can hold the new epic gems)

it seems like the alchemy one will be all the time. i guess it is the same as alchemists already get a buff to their flasks. its only usable by max lvl alchemists (high lvl), so if you can use it you can make your own. im guessing bop. over the course of a week, thats going to save you 12 flasks. lealla can tell you what that cost is.

There is more to life than pew pew you know, like staying out of the fire so you can live to pew pew another day

We've picked up some more details about professions in Patch 3.2. Some of the changes were covered a few days ago by Eliah. The notes made today elaborate more on engineering, alchemy, fishing and cooking changes.

Alchemy

Stackable potions now stack to 20.

Five new epic gem transmute recipes are available from the Northrend trainer. The recipe for transmuting a Cardinal Ruby can be learned from a quest, given by Linzy Blackbolt in Dalaran.
Rage potions can now be used by druids.

I have an entire guild bank tab filled with nothing but Mana Injectors. I was both saddened and delighted when I heard that potions now stack to 20. Big plus to Potion of Speed and Potion of Wild Magic since those will be stackable now. But are they going to be completely useless? Nope! Wait until you see the Engineering changes. It means I don't have to make any more injectors! New epic gem transmutes are on the way too!

More profession changes after the jump.

Cooking

Blackened Dragonfin Recipe: Now only requires 1 Dragonfin Angelfish.

Chef's Hat is now superior-quality and allows the chef to cook faster.

The Ultrasafe Bullet Machine and Saronite Arrow Maker schematics have been simplified to create a full stack of the appropriate ammunition. No longer requires an anvil. Reduced the materials required to make this ammunition.

Mote Extractor now has innate tracking for gas clouds while it is in your inventory. Tracking of gas clouds has been removed from goggles.

Potion Injectors now increase the amount gained by 25% when used by engineers. Quantity produced by recipes for Runic Healing and Mana Injectors has been increased.

Transporter devices are no longer classified as trinkets and can be used directly from your inventory.

Reduced the materials needed to create all engineering Dragonlings, and reduced their cooldowns, although they still cannot be used in Arenas.

Here we go! The most hotly debated profession gets several changes to it. I mentioned earlier about the changes to potion injectors. It seems like engineers who use injectors now get a bonus out of it. As a healer, I can't help but wonder if that alone is worth a profession switch. Then I remembered what a grind leveling engineering was and thought better of it. But at least injectors aren't going to be completely useless anymore.

Fishing

Players with 300 or higher cooking have a chance to find a Waterlogged Recipe in the Bag of Fishing Treasures awarded by the Northrend fishing dailies. This item can be traded to other players and rewards several Dalaran Cooking Rewards when turned in.

Inscription

Added a new Glyph of Claw for young feral druids who haven't yet obtained Mangle. Inscribers can learn this glyph from the trainer.

hmmm... engineers will get more from their mana/health pots that are injectors. i like it. also get more from the recepie.... does that mean i'm going to get 25 injector charges for the price of 20 pots? if so thats pimp. and engineerings is definatly tons more awesome than it is now.

There is more to life than pew pew you know, like staying out of the fire so you can live to pew pew another day

Blah. Flask of the North is +47 sp/+80 AP/+40 Str (link). It's obviously intended just to offset the bonuses other professions get in Arenas, and not to be a single uber flask for Alchies to carry around everywhere.

Also of note: Alchemists will be able to transmute rare gems into the new epic gems.